The disclosure generally relates to an AC-to-DC power converter and, more particularly, to an AC-to-DC power converter capable of reducing the required capacitance of the input capacitor and related control circuits.
An input capacitor is required to be arranged in an AC-to-DC power converter to stabilize a rectified voltage generated by a rectifier, and the input capacitor must has a rated voltage higher than a peak value of the AC voltage received by the AC-to-DC power converter. Accordingly, if the AC-to-DC power converter has to support a wider range of the input AC voltage, it requires the input capacitor to have a larger capacitance.
For example, if the AC-to-DC power converter has to support an AC voltage ranging from 90 volts to 380 volts, the peak value of the AC voltage may up to nearly 537 volts. In this situation, an input capacitor whose rated voltage is higher than the aforementioned peak value is required by the AC-to-DC power converter in order to satisfy the design requirements. As a result, it not only significantly increases the circuit area, total weight, and hardware cost, but also increases the hardware requirement of the components inside the AC-to-DC power converter, and thereby increasing the circuitry design difficulty of the AC-to-DC power converter.